"Neon Neon is a chemical element with symbol Ne and atomic number 10. It is a noble gas. Neon is a colorless, odorless, inert monatomic gas under standard conditions, with about two-thirds the density of air. It was discovered (along with krypton and xenon) in 1898 as one of the three residual rare inert elements remaining in dry air, after nitrogen, oxygen, argon and carbon dioxide were removed. Neon was the second of these three rare gases to be discovered and was immediately recognized as a new element from its bright red emission spectrum. The name neon is derived from"
"Nobelium Nobelium is a synthetic chemical element with symbol No and atomic number 102. It is named in honor of Alfred Nobel, the inventor of dynamite and benefactor of science. A radioactive metal, it is the tenth transuranic element and is the penultimate member of the actinide series. Like all elements with atomic number over 100, nobelium can only be produced in particle accelerators by bombarding lighter elements with charged particles. A total of twelve nobelium isotopes are known to exist; the most stable is No with a half-life of 58 minutes, but the shorter-lived No (half-life 3.1 minutes) is"
"the material was known in ancient times, while for others, the name is a more recent invention. For example, ""He"" is the symbol for helium (New Latin name, not known in ancient Roman times), ""Pb"" for lead (""plumbum"" in Latin), and ""Hg"" for mercury (""hydrargyrum"" in Greek). Some symbols come from other sources, like ""W"" for tungsten (""Wolfram"" in German, not known in Roman times). Temporary symbols assigned to newly or not-yet synthesized elements use 3-letter symbols based on their atomic numbers. For example, ""Uno"" was the temporary symbol for hassium (element 108) which had the temporary name of ""unniloctium""."
"the Greek word, , neuter singular form of (""neos""), meaning new. Neon is chemically inert, and no uncharged neon compounds are known. The compounds of neon currently known include ionic molecules, molecules held together by van der Waals forces and clathrates. During cosmic nucleogenesis of the elements, large amounts of neon are built up from the alpha-capture fusion process in stars. Although neon is a very common element in the universe and solar system (it is fifth in cosmic abundance after hydrogen, helium, oxygen and carbon), it is rare on Earth. It composes about 18.2 ppm of air by volume"
"Group 10 element Group 10, numbered by current IUPAC style, is the group of chemical elements in the periodic table that consists of nickel (Ni), palladium (Pd), platinum (Pt), and perhaps also the chemically uncharacterized darmstadtium (Ds). All are d-block transition metals. All known isotopes of darmstadtium are radioactive with short half-lives, and are not known to occur in nature; only minute quantities have been synthesized in laboratories. Like other groups, the members of this group show patterns in electron configuration, especially in the outermost shells, although for this group they are particularly weak, with palladium being an exceptional case."
"lines which Lockyer had observed: helium. Prior to this, Ramsay had already isolated a new gas from the atmosphere; argon, with an atomic weight of 40. A problem now arose – Mendeleev had not left any gaps which were suitable for either of these two new elements, which led Ramsay to conclude an entire group was missing from the periodic table – only two of whose members were now known to exist, helium and argon. Ramsey successfully discovered all the other stable elements in the group which he named neon (Greek for new), krypton (Greek for hidden) and xenon (Greek"
"Neodymium Neodymium is a chemical element with symbol Nd and atomic number 60. It is a soft silvery metal that tarnishes in air. Neodymium was discovered in 1885 by the Austrian chemist Carl Auer von Welsbach. It is present in significant quantities in the ore minerals monazite and bastnäsite. Neodymium is not found naturally in metallic form or unmixed with other lanthanides, and it is usually refined for general use. Although neodymium is classed as a rare earth, it is a fairly common element, no rarer than cobalt, nickel, or copper, and is widely distributed in the Earth's crust. Most"
"Selenium Selenium is a chemical element with symbol Se and atomic number 34. It is a nonmetal (more rarely considered a metalloid) with properties that are intermediate between the elements above and below in the periodic table, sulfur and tellurium, and also has similarities to arsenic. It rarely occurs in its elemental state or as pure ore compounds in the Earth's crust. Selenium (from Ancient Greek (selḗnē) ""Moon"") was discovered in 1817 by Jöns Jacob Berzelius, who noted the similarity of the new element to the previously discovered tellurium (named for the Earth). Selenium is found in , where it"
"Many scientists in the field called it ""element 117"", with the symbol ""E117"", ""(117)"", or ""117"". According to guidelines of IUPAC valid at the moment of the discovery approval, the permanent names of new elements should have ended in ""-ium""; this included element 117, even if the element was a halogen, which traditionally have names ending in ""-ine""; however, the new recommendations published in 2016 recommended using the ""-ine"" ending for all new group 17 elements. The IUPAC guidelines specify that the discovery team has naming rights for the element. After the original synthesis in 2010, Dawn Shaughnessy of LLNL"
"of metals. Cu comes from Cuprum, Fe comes from Ferrum, Ag from Argentum. The symbols were not followed by a period (full stop) as with abbreviations. Later chemical elements were also assigned unique chemical symbols, based on the name of the element, but not necessarily in English. For example, sodium has the chemical symbol 'Na' after the Latin ""natrium"". The same applies to ""W"" (wolfram) for tungsten, ""Fe"" (ferrum) for iron, ""Hg"" (hydrargyrum) for mercury, ""Sn"" (stannum) for tin, ""K"" (kalium) for potassium, ""Au"" (aurum) for gold, ""Ag"" (argentum) for silver, ""Pb"" (plumbum) for lead, ""Cu"" (cuprum) for copper, and"
"spectrum of the sun (it is not known why the suffix ""-ium"", which is used for metals, was chosen). The other noble gases are neon (""new""), argon (""slow, lazy""), krypton (""hidden""), xenon (""stranger""), and radon (""from radium""). Many more elements have been given names that have little or nothing to do with their properties. Elements have been named for celestial bodies (helium, selenium, tellurium, for the sun, moon, and earth; cerium and palladium for Ceres and Pallas, two asteroids). They have been named for mythological figures, including Titans in general (titanium) and Prometheus in particular (promethium); Roman and Greek gods"
"Hassium Hassium is a synthetic chemical element with symbol Hs and atomic number 108. It is named after the German state of Hesse. It is a synthetic element and radioactive; the most stable known isotope, Hs, has a half-life of approximately 10 seconds. In the periodic table of the elements, it is a d-block transactinide element. Hassium is a member of the 7th period and belongs to the group 8 elements: it is thus the sixth member of the 6d series of transition metals. Chemistry experiments have confirmed that hassium behaves as the heavier homologue to osmium in group 8."
"can cause violent oxidation of organic material. Nitrogen Nitrogen is a chemical element with symbol N and atomic number 7. It was first discovered and isolated by Scottish physician Daniel Rutherford in 1772. Although Carl Wilhelm Scheele and Henry Cavendish had independently done so at about the same time, Rutherford is generally accorded the credit because his work was published first. The name ""nitrogène"" was suggested by French chemist Jean-Antoine-Claude Chaptal in 1790, when it was found that nitrogen was present in nitric acid and nitrates. Antoine Lavoisier suggested instead the name azote, from the Greek άζωτικός ""no life"", as"
"is possibly a Jules Verne quote. The crater Mendeleev on the Moon, as well as element number 101, the radioactive mendelevium, are named after him. In 1863 there were 56 known elements with a new element being discovered at a rate of approximately one per year. Other scientists had previously identified periodicity of elements. John Newlands described a Law of Octaves, noting their periodicity according to relative atomic weight in 1864, publishing it in 1865. His proposal identified the potential for new elements such as germanium. The concept was criticized and his innovation was not recognized by the Society of"
"Neptunium Neptunium is a chemical element with symbol Np and atomic number 93. A radioactive actinide metal, neptunium is the first transuranic element. Its position in the periodic table just after uranium, named after the planet Uranus, led to it being named after Neptune, the next planet beyond Uranus. A neptunium atom has 93 protons and 93 electrons, of which seven are valence electrons. Neptunium metal is silvery and tarnishes when exposed to air. The element occurs in three allotropic forms and it normally exhibits five oxidation states, ranging from +3 to +7. It is radioactive, poisonous, pyrophoric, and can"
"Nitrogen Nitrogen is a chemical element with symbol N and atomic number 7. It was first discovered and isolated by Scottish physician Daniel Rutherford in 1772. Although Carl Wilhelm Scheele and Henry Cavendish had independently done so at about the same time, Rutherford is generally accorded the credit because his work was published first. The name ""nitrogène"" was suggested by French chemist Jean-Antoine-Claude Chaptal in 1790, when it was found that nitrogen was present in nitric acid and nitrates. Antoine Lavoisier suggested instead the name azote, from the Greek άζωτικός ""no life"", as it is an asphyxiant gas; this name"
"silicon, and aluminium. By analyzing all three isotopes, the cosmogenic component can be resolved from magmatic neon and nucleogenic neon. This suggests that neon will be a useful tool in determining cosmic exposure ages of surface rocks and meteorites. Similar to xenon, neon content observed in samples of volcanic gases is enriched in Ne and nucleogenic Ne relative to Ne content. The neon isotopic content of these mantle-derived samples represents a non-atmospheric source of neon. The Ne-enriched components are attributed to exotic primordial rare-gas components in the Earth, possibly representing solar neon. Elevated Ne abundances are found in diamonds, further"
"came to realize that it also contained a new element, which he named selenium after the Greek moon goddess Selene. Three of the chalcogens (sulfur, selenium, and tellurium) were part of the discovery of periodicity, as they are among a series of triads of elements in the same group that were noted by Johann Wolfgang Döbereiner as having similar properties. Around 1865 John Newlands produced a series of papers where he listed the elements in order of increasing atomic weight and similar physical and chemical properties that recurred at intervals of eight; he likened such periodicity to the octaves of"
"gas of hydrogen and neon in a strong electric field, ions are formed that are called neides. Ions observed include TiNe, TiHNe, ZnNe , ZrNe, NbNe, NbHNe, MoNe, RhNe, PdNe, TaNe, WNe, WNe, ReNe, IrNe, AuNe (possible). SiFNe can be made from neon and using mass spectrometer technology. SiFNe has a bond from neon to silicon. has a very weak bond to fluorine and a high electron affinity. NeCCH, a substituted acetylene, is predicted to be energetically stable by 5.9 kcal/mol, one of the most stable organic ions. Metal ions can attract multiple neon atoms to form clusters. The shape"
"be named with the ending ""-ium"", even if they turned out to be halogens (traditionally ending in ""-ine"") or noble gases (traditionally ending in ""-on""). While the provisional name ununoctium followed this convention, a new IUPAC recommendation published in 2016 recommended using the ""-on"" ending for new group 18 elements, regardless of whether they turn out to have the chemical properties of a noble gas. In June 2016 IUPAC announced that the discoverers planned to give the element the name ""oganesson"" (symbol: ""Og""), in honour of the Russian nuclear physicist Yuri Oganessian, a pioneer in superheavy element research for sixty"
"in 1938, it was realized that Fermi's discovery was actually a mixture of barium, krypton, and other elements. The actual element was discovered several years later, and assigned the name neptunium. Fascist authorities wanted one of the elements to be named ""littorio"" after the Roman ""lictores"" who carried the ""fasces"", a symbol appropriated by Fascism. Ausonium Ausonium (atomic symbol Ao) was the name assigned to the element with atomic number 93, now known as neptunium. It was named after a Greek name of Italy, Ausonia. The same team assigned the name hesperium to element 94, after Hesperia, a poetic name"
"be used as placeholders until permanent names were established; under it, element 105 would be ""unnilpentium"", from the Latin roots ""un-"" and ""nil-"" and the Greek root ""pent-"" (meaning ""one"", ""zero"", and ""five"", respectively, the digits of the atomic number). Both teams ignored it as they did not wish to weaken their outstanding claims. In 1981, the Gesellschaft für Schwerionenforschung (GSI; ""Society for Heavy Ion Research"") in Darmstadt, West Germany, claimed synthesis of element 107; their report came out five years after the first report from JINR but with greater precision, making a more solid claim on discovery. GSI acknowledged"
"Ausonium Ausonium (atomic symbol Ao) was the name assigned to the element with atomic number 93, now known as neptunium. It was named after a Greek name of Italy, Ausonia. The same team assigned the name hesperium to element 94, after Hesperia, a poetic name of Italy. (Element 94 was later named plutonium). The discovery of the element, now discredited, was made by Enrico Fermi and a team of scientists at the University of Rome in 1934. In the same year Ida Noddack had already presented alternative explanations for the experimental results of Fermi. Following the discovery of nuclear fission"
"H) to 109 (unnilennium, Une). The list given in ISO 31-8:1992 was quoted from the 1998 IUPAC ""Green Book"" Quantities, Units and Symbols in Physical Chemistry and adds in some cases in parentheses the Latin name for information, where the standard symbol has no relation to the English name of the element. Since the 1992 edition of the standard was published, some elements with atomic number above 103 have been discovered and renamed. Symbols for chemical elements shall be written in roman (upright) type. The symbol is not followed by a full-stop. Examples: Attached subscripts or superscripts specifying a nucleotide"
"Ununennium Ununennium, also known as eka-francium or simply element 119, is the hypothetical chemical element with symbol Uue and atomic number 119. ""Ununennium"" and ""Uue"" are the temporary systematic IUPAC name and symbol respectively, until a permanent name is decided upon. In the periodic table of the elements, it is expected to be an s-block element, an alkali metal, and the first element in the eighth period. It is the lightest element that has not yet been synthesized. Experiments aimed at the synthesis of ununennium began in December 2017 at RIKEN in Japan; another attempt by the team at the"
"Mendeleev. Other calculated information was obtained by Henry Moseley in 1914. In 1908, Japanese chemist Masataka Ogawa announced that he had discovered the 43rd element and named it ""nipponium"" (Np) after Japan (""Nippon"" in Japanese). However, recent analysis indicated the presence of rhenium (element 75), not element 43, although this reinterpretation has been questioned by Eric Scerri. The symbol Np was later used for the element neptunium, and the name ""nihonium"", also named after Japan, along with symbol Nh, was later used for element 113. Element 113 was also discovered by a team of Japanese scientists and was named in"
"to be eka-antimony, but was soon convinced that it was instead eka-silicon. Before Winkler published his results on the new element, he decided that he would name his element ""neptunium"", since the recent discovery of planet Neptune in 1846 had similarly been preceded by mathematical predictions of its existence. However, the name ""neptunium"" had already been given to another proposed chemical element (though not the element that today bears the name neptunium, which was discovered in 1940). So instead, Winkler named the new element ""germanium"" (from the Latin word, ""Germania"", for Germany) in honor of his homeland. Argyrodite proved empirically"
"71, 89, 115, 123, 147, 161, ... are stable to beta decay (see Beta-decay stable isobars). Only two stable nuclides have fewer neutrons than protons: hydrogen-1 and helium-3. Neutron number The neutron number, symbol N, is the number of neutrons in a nuclide. Atomic number (proton number) plus neutron number equals mass number: Z+N=A. The difference between the neutron number and the atomic number is known as the neutron excess: D = N - Z = A - 2Z. Neutron number is rarely written explicitly in nuclide symbol notation, but appears as a subscript to the right of the element"
"or an electrophile; similarly ""Nu"" denotes a nucleophile. ""L"" is used to represent a general ligand in inorganic and organometallic chemistry. ""M"" is also often used in place of a general metal. At least two additional, two-letter generic chemical symbols are also in informal usage, ""Ln"" for any lanthanide element and ""An"" for any actinide element. ""Rg"" was formerly used for any rare gas element, but the group of rare gases has now been renamed noble gases and the symbol ""Rg"" has now been assigned to the element roentgenium. Isotopes are distinguished by the atomic mass number (total protons and"
"Niobium, or columbium, is a chemical element with the symbol Nb and atomic number 41. It is a soft, grey, ductile transition metal, which is often found in the pyrochlore mineral, the main commercial source for niobium, and columbite. The name comes from Greek mythology: ""Niobe"", daughter of ""Tantalus"". Niobium has physical and chemical properties similar to those of the element tantalum, and the two are therefore difficult to distinguish. The English chemistCharles Hatchett reported a new element similar to tantalum in 1801, and named it columbium. In 1809, the English chemist William Hyde Wollaston wrongly concluded that tantalum and"
"gas. Neon has three stable isotopes: Ne (90.48%), Ne (0.27%) and Ne (9.25%). Ne and Ne are partly primordial and partly nucleogenic (i.e. made by nuclear reactions of other nuclides with neutrons or other particles in the environment) and their variations in natural abundance are well understood. In contrast, Ne (the chief primordial isotope made in stellar nucleosynthesis) is not known to be nucleogenic or radiogenic. The causes of the variation of Ne in the Earth have thus been hotly debated. The principal nuclear reactions generating nucleogenic neon isotopes start from Mg and Mg, which produce Ne and Ne respectively,"
"from the French ""nitre"" (potassium nitrate, also called saltpeter) and the French suffix ""-gène"", ""producing"", from the Greek -γενής (-genes, ""begotten""). Chaptal's meaning was that nitrogen is the essential part of nitric acid, which in turn was produced from niter. In earlier times, niter had been confused with Egyptian ""natron"" (sodium carbonate) – called νίτρον (nitron) in Greek – which, despite the name, contained no nitrate. The earliest military, industrial, and agricultural applications of nitrogen compounds used saltpeter (sodium nitrate or potassium nitrate), most notably in gunpowder, and later as fertiliser. In 1910, Lord Rayleigh discovered that an electrical discharge"
"the Greek word ""khalkόs"" (χαλκός) principally meaning copper (the term was also used for bronze/brass, any metal in the poetic sense, ore or coin), and the Latinised Greek word ""genēs"", meaning ""born"" or ""produced"". Sulfur has been known since antiquity, and oxygen was recognized as an element in the 18th century. Selenium, tellurium and polonium were discovered in the 19th century, and livermorium in 2000. All of the chalcogens have six valence electrons, leaving them two electrons short of a full outer shell. Their most common oxidation states are −2, +2, +4, and +6. They have relatively low atomic radii,"